Strip Module Working Group Meeting 16 th May 2012 Hybrids A Greenall

Outline ABCN-25 Shield-less hybrid Changes being made Current status Serial Powering of Modules Latest results with “Chain of Modules” configuration for a single module ABC130 First pass at Pad ring Iterative process between hybrid and asic designers – converging to a preferred geometry See Francis’s talk... Irradiation of new family of NTCs Prerequisite for use with HCC 1

2 Primarily being used as a test vehicle for differing flavoured hybrid attachment tabs Trying to identify a tab which does not compromise the planarity of the hybrid after reflow Each of the 8 hybrids, on a panel, comes with a different flavoured tab Tabs differ in geometry, builds (Cu inlay) and cut profile Other changes taken on board Hybrid build now reduced to 4 layers (5 th shield layer dropped) Use of blind vias through out Final opportunity to confirm that shield is not needed before we move to ABCN130 Other (minor) changes taken on board: Wshunt disable line now hard-wired to VDD (no longer bussed) CLKmode80 hard-wired to VDD on panel (fixed to 80MHz Dclk) Mshunt VDD monitor point now revised so that 3 (mutually exclusive) locations are now available Far-end (as before), centre of hybrid or hybrid power entry – set by wire bond Via chains added to panel – allows QA of vias by use of (4-wire) resistance measurement 3 chains added of ~190 vias/chain Via connections monitored are L1-L2, L1-L3 and L1-L4 Minor changes to solder resist (requested by Forest at SCIPP) Hybrid NTCs are now brought out to 0.1” connector on panel (one per hybrid location) for monitoring Layout and drill files for manufacture now complete Will go for submission this week ABCN-25 Shield-less Hybrid

Serial Powering of Modules Request to implement “Chain of Modules” powering configuration in more sanitary manner PCB designed, based on PPB geometry STAR topology implemented for both power and return (centred on hybrid power feeds and not PCB) Provides serial powered configuration for a module i.e. not serial powering of hybrids Results in 2.5V (~10A) across module PPB Replacement (PPBR) SPin SPou t SPinSPout STAR Point Hybrid Power Return Pi-filter 2.5V/10A SPout SPin V+ V- V+ V- 2 x 10µF22µF 12nH 2 x 10µF22µF 12nH 3

Double Trigger Noise (DTN) Results 1fC AC0.75fC AC0.5fC AC1fC DC0.5fC DC Hybrid Hybrid Hybrid Hybrid fC AC Results obtained with Hybrids 2/3 AC referenced to sensor – they should be DC Hybrids now DC referenced occupancy globally reduced Hybrid 0 Hybrid 1 Hybrid 2 Hybrid 3 Went through series of incremental changes – goal is to make electrical configuration as per new Bus cable Identified 2 nd HV connection missing off “low side “ hybrid - adding this connection brought occupancy down dramatically Both 1fC & 0.5fC clean (0 hits) At 0.5fC record 29, 114, 907 and 593 hits (hybrids 0 to 3 respectively) Added 2 nd “shield” connection to the cooling block at the BCC end, followed by 2 nd sensor HV contact 1fC0.75fC0.5fC Hybrid Hybrid Hybrid Hybrid BCC shield connection only Adding 2 nd sensor HV contact 0.5fC AC Still see evidence of noise bands – see DTN plot 4 Out of the box results

But DTN doesn’t tell the whole story... Input noise of module was originally high with normal grounding test configuration Input noise with PPBR and DC referenced hybrids – comparable to seen in the past with elevated noise Input noise with PPBR with both ends of hybrids referenced to cooling block With 2 nd sensor HV contact Global reduction of ≥50e is now achieved compared to original 5 Noise reduction of ~40e achieved

Irradiation of Hybrid NTCs for future ABC130 modules Request from ASIC designers to revise NTC type such that the resistance at 25°C is 1kΩ HCC temperature measuring circuit has a leakage current which introduces a DC offset NTCs with high R could be problematic for measurement NTCs used on present hybrids are 10kΩ Switching to different NTC will require their qualification to expected Upgrade radiation dose 3 candidate manufacturers identified: Murata, Vishay and Panasonic Current family of devices, manufactured by Semitec, don’t go below 10kΩ Plan to irradiate the following devices plus reference, vis: 5 x 1kΩ and 5 x 2kΩ - from each manufacturer 30 off total 5 x Semitec (reference) Devices will be hooked up to a multiplexed data logger for real time measurement during irradiation To be done at CERN PS (July/August) and possibly the irradiation facility at Birmingham Irradiation of new family of NTCs 6

ABCN-25 shield-less hybrid is now more or less ready for submission Issue of planarity of tabs is being addressed Will come as a 4 layer build – no shield (preparing for the future ABC130 hybrids) Other minor changes taken on board (see list on slide 2 ) Serial Powering of modules – configured as “Chain of Modules” PCB designed with “star” topology has been demonstrated to work Incremental changes to electrical configuration showed improving noise performance Changes reflect configuration of new bus cables The future for a stavelet with this adopted configuration looks promising ABC130 first pass at Pad Ring has been done Preliminary layout has been demonstrated to fit within the asic geometry of 6mm x 7.9mm Irradiation of new family of NTCs Candidate families of NTCs with lower resistance at 25°C have been identified (1kΩ at 25°C, present NTCs are 10kΩ at 25°C) Requested for matching up to current HCC design Will go for irradiation in summer to qualify their robustness to radiation damage Summary 7